Sixty-two human immunodeficiency virus (HIV) controllers (6 elite and 56 viremic controllers) in the US Military Department of Defense HIV Natural History Study cohort initiated highly active antiretroviral therapy (HAART) and achieved statistically significant mean CD4 cell count increases, although the gains were lower than those in treated noncontrollers. HIV controllers experienced CD4 cell count reconstitution with HAART regardless of pretherapy viral load, including patients with undetectable viral loads at HAART initiation.